Hi Mike,

Thanks for the hose-check suggestion. I have suspected poor
circulation through the radiator, as the high speed fan kicks on at
McDonald's on pretty cool days.

Will also check out David's pressure cap test.

I am especially freaked out about the differential cooler, as this
failure caused coolant to go into my transmission (as well as trans
fluid into my cooling system).

My mechanic still has the part at his shop - I may go back and look
at it. I suppose it's possible that the leak occurred "around" the
gaskets, rather than through the metal????

I was thinking about excessive heat. Maybe having the thermostat
checked too, but I remember I had a new one last winter (half way
into this big mess).

Thanks!
Paul

>Could you possibly have a crimped hose or tube somewhere that's causing
>undo pressure in the system?  Maybe you should trace all the hoses and
>make sure.  Sounds like a real drag!
>
>                                                             Mike G.
>
>Paul Cavanaugh wrote:
>
>>  My 1990 (180k miles) GL automatic just had it's 4th rear heater core
>>  burst in 12 months!
>>
>>  It also has burst two (metal) differential coolers, flooding coolant
>>  into and ruining my transmission.
>>
>>  Any ideas what could be happening?
>>
>>  My friends are urging my to give up the car (and I am tired of
>>  pulling up the flooded carpet)!
>>
>>  Thanks!
>>  Paul

--
'90 Vanagon (180k)
'84 Vanagon (217k)
'78 Microbus (175k)